A honeycomb-like monolayer of HfO2 and the calculation of static dielectric constant eliminating the effect of vacuum spacing

2018 ◽  
Vol 20 (41) ◽  
pp. 26453-26462 ◽  
Author(s):  
Junhui Weng ◽  
Shang-Peng Gao
Keyword(s):  
Dielectric Constant ◽  
First Principles ◽  
Dielectric Material ◽  
Static Dielectric Constant ◽  
First Principles Calculations

A novel dielectric material of monolayer 1T-HfO2 has been investigated using first-principles calculations.

Phonons and static dielectric constant inCaTiO3from first principles

2000 ◽  
Vol 62 (6) ◽  
pp. 3735-3743 ◽  
Author(s):  
Eric Cockayne ◽  
Benjamin P. Burton
Keyword(s):  
Dielectric Constant ◽  
First Principles ◽  
Static Dielectric Constant

Graphene Adsorbed on Corundum Surface: Clean Interface and Band Gap Opening

2012 ◽  
Vol 1407 ◽  
Author(s):  
Bing Huang ◽  
Qiang Xu ◽  
Su-Huai Wei
Keyword(s):  
Band Gap ◽  
First Principles ◽  
Gate Dielectric ◽  
Dielectric Material ◽  
First Principles Calculations ◽  
Structural And Electronic Properties ◽  
Gap Opening ◽  
Clean Interface ◽  
Injection Barrier ◽  
Gate Dielectric Material

ABSTRACTUsing advanced first-principles calculations, we have studied the structural and electronic properties of graphene/α-Al2O3 interfaces and show that α -Al2O3 is an ideal gate dielectric material for graphene transistors. Clean interface exists between graphene and Al-terminated (or hydroxylated) Al2O3 and the valence band offsets for these systems are large enough to create injection barrier. Remarkably, a band gap of ~180 meV can be induced in graphene layer adsorbed on Al-terminated surface, which is significantly larger than graphene on other popular substrates.

First-Principles Calculations of the Dielectric Constant for the GeO2 Films

2011 ◽  
Vol 470 ◽  
pp. 60-65 ◽  
Author(s):  
Masahiro Tamura ◽  
Jun Nakamura ◽  
Akiko Natori
Keyword(s):  
Dielectric Constant ◽  
Electric Fields ◽  
Ground State ◽  
First Principles ◽  
Rutile Phase ◽  
Dielectric Constants ◽  
Ionic Character ◽  
First Principles Calculations ◽  
External Electric Fields ◽  
Static Dielectric Constants

Dielectric properties of α-quartz and rutile-GeO2 thin-films are investigated using first-principles ground-state calculations in external electric fields. The optical and the static dielectric constants inside the films have nearly-constant values, corresponding to their bulk values, while only at the topmost surface layer the dielectric constants decrease distinctly. It has been found that the dielectric constant for the rutile-GeO2 is larger than that for the α-quartz one, which stems from the larger ionic character of the Ge-O bond for the rutile phase.

Electronic Structure and X-ray Absorption Spectra of Rutile TiO2 Using First-Principles Calculations

2014 ◽  
Vol 52 (12) ◽  
pp. 1025-1029
Author(s):  
Min-Wook Oh ◽  
Tae-Gu Kang ◽  
Byungki Ryu ◽  
Ji Eun Lee ◽  
Sung-Jae Joo ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Absorption Spectra ◽  
First Principles ◽  
First Principles Calculations ◽  
Rutile Tio2 ◽  
X Ray ◽  
X Ray Absorption

To Bend or Not to Bend, the Dilemma of Multiple Bonds

2019 ◽  
Author(s):  
Michele Pizzocchero ◽  
Matteo Bonfanti ◽  
Rocco Martinazzo
Keyword(s):  
First Principles ◽  
2D Materials ◽  
Main Group ◽  
First Principles Calculations ◽  
Group 14 ◽  
Multiple Bonds ◽  
Main Group Elements ◽  
Structural Distortions

The manuscript addresses the issue of the structural distortions occurring at multiple bonds between high main group elements, focusing on group 14. These distortions are known as trans-bending in silenes, disilenes and higher group analogues, and buckling in 2D materials likes silicene and germanene. A simple but correlated \sigma + \pi model is developed and validated with first-principles calculations, and used to explain the different behaviour of second- and higher- row elements.

Thermodynamic Stability of Hexagonal and Rhombohedral Bn at Cvd Conditions from Van der Waals Corrected First Principles Calculations

2019 ◽  
Author(s):  
Henrik Pedersen ◽  
Björn Alling ◽  
Hans Högberg ◽  
Annop Ektarawong
Keyword(s):  
Thin Films ◽  
Thermodynamic Stability ◽  
First Principles ◽  
Thermal Equilibrium ◽  
Density Functional ◽  
Van Der Waals ◽  
Chemical Vapor ◽  
First Principles Calculations ◽  
Functional Theory ◽  
The Stability

Thin films of boron nitride (BN), particularly the sp<sup>2</sup>-hybridized polytypes hexagonal BN (h-BN) and rhombohedral BN (r-BN) are interesting for several electronic applications given band gaps in the UV. They are typically deposited close to thermal equilibrium by chemical vapor deposition (CVD) at temperatures and pressures in the regions 1400-1800 K and 1000-10000 Pa, respectively. In this letter, we use van der Waals corrected density functional theory and thermodynamic stability calculations to determine the stability of r-BN and compare it to that of h-BN as well as to cubic BN and wurtzitic BN. We find that r-BN is the stable sp<sup>2</sup>-hybridized phase at CVD conditions, while h-BN is metastable. Thus, our calculations suggest that thin films of h-BN must be deposited far from thermal equilibrium.

Sign in / Sign up

Export Citation Format

Share Document